Bebo7500. I've also bought this extension a short while ago and was having that problem, but I think I got around it.

In my case, the thumbnails wouldn't appear while the parameter "Introtext Item" in the Module Options had the value "2". I increased this value and the thumbnails started appearing. Hope it works for you too.

Hi bebo, I think the problem is because the image file names contain spaces on it, and the module unable to process it to generate the thumbnail. Please try to rename the image filenames with no spaces in it.